discussion FDM PLA 3D printing - with a model making inclination

[Dave Ward]

Assembling the Sunlu T3 printer took about half an hour - 10 bolts, four of which were for the spool holder!
It has a bed size comparable to the Anet, the frame is aluminium extrusions & the body of sheet steel. It has a Bowden style feed, with an all-metal geared extruder. The power supply gives 24V, and heats up the bed & nozzle very quickly. It took me a while to work out the sequence of levelling the bed, the instructions seem to be counter intuitive! It's now set, and before each print it does a 15 point check of the bed height & compenates. First print I did was rubbish - the printer clattered and groaned, but was very fast. I found that I had not unchecked the 'fast print' mode in the printer menu, and it was printing at 3 or 4 times the normal speed! Now, it is printing - it's very quiet, most noise is from the cooling fans! You are allegedly able to print at 200mm/sec, but the quality would be rubbish. I've been printing at 80mm/sec - twice the speed of the Anet. I still need to tweak the settings to improve the finishes & reduce stringing, but that shouldn't take too long. I'll put up some pictures tomorrow.
Dave

 

[Neil Merryweather]

You're really becoming quite a pro now Dave:hugging-face:

 

[Guest]

Keep following but have no real idea of what's been done, seems very much like a printer when it has a turn .
Definitely going to be the big thing in years to come for modellers with a flair for engineering and computing skills .

 

[Dave Ward]

Here it is, in operation as I said the printer itself is quiet ( silent steppers ), but the fans are not, and they cut in and out as needed!
The first thing I printed out after initial false starts was this an Admiralty Armed Trawler in 1/700 printed at 0.2mm layer height
A bit rough, but the shapes there................
A few tweaks, and .........

Printed at 0.15mm layer height - took about 90 minutes to print
In close up, the layers are nice & even - the height of the bows is around 7mm

I can print down to <0.1mm layer height, but the time of print increases.
I'll give these a lick of primer & see how they look.
I don't tend to print benchmarks - I prefer to see the results on something I actually want to print. They're OK if you want to compare printers, but I want to see results on a real model
Dave

 

[Jim R]

Those few tweaks have definitely made an improvement.

 

[Dave Ward]

After a quick coat of primer - the better of the two trawlers,,,,,,,,,,,,

What I would do is carerfully go round the model & remove all sharp edges, strings & other artefacts before painting, but this is still the process of trying to find the best settings for the Sunlu.
It's now in the process of printing something else
Guess what it is yet?
Dave

 

[Tim Marlow]

Stingray?

 

[Dave Ward]

Yes! - A four part model of Stingray - scale?, well your guess is as good as mine!
Dave

 

[Dave Ward]

Another lesson confirmed! I'd finished my Stingray & decided that there wasn't enough filament on the spool for my next print. I decided, on the grounds of economy, to revisit a spool of filament that I'd had problems with on the Anet. I thought that with the Sunlu it might be more forgiving. Now, with dismal failures on two printers, I can say this stuff is garbage! Today, it wouldn't stick, I re- levelled the build plate, tweaked the temperatures - it began to stick, but in the middle of a nice line of print, it would start to 'blob' and miss patches & then, when adding another layer, it'd begin to pull the whole lot up. I tried a different software slicer, but finally admitted defeat. It was an unbranded satin white PLA. I opened a brand new packet of JAYO grey PLA - and the printer happily started working properly.
I've been under the weather recently, and must admit I was getting a bit discouraged with the white PLA, but the new spool has lifted my mood a bit.
I was trying to print a 1/35 AMC 35 - a French 30's cavalry tank, but that's now the plan for tomorrow - the printer is working on a 1/700 floaty thing...............
Dave

 

[Dave Ward]

This is a 1/700 USS Independence - a 'littoral combat ship' essentially a hull with two outriggers & the deck built across them

Has proved to be problematical, and has been laid up, after less than ten years service.....................
Modern ships don't lend to be suitable for FDM printing - too many aerials, and lattice masts - this print lost the fwd gun barrel, a radar mast & the Phalanx CIWS. - Just too delicate - and it shows 'quilting' in places - I'd reduced the % infill & surface layers to cut the print time - not clever.
This the start of the print of the hull of the AMC 35 ( going to take 7 hours ).......................

I'm happy to say the layers are sticking & going down evenly - a big contrast to the total mess I had yesterday!
Dave

 

[Dave Ward]

sigh - it looks like my printer purchase from China has vanished - it was supposedly despatched from China, but now has disappeared..............

Had an update from AliExpress they've validated my claim for a refund due to 'Abnormal Shipping' & they'll issue that within the next three days. It seems from the rapid progress, that this seller has a bit of history..............
Dave

 

[Dave Ward]

After 7 hours 18 minutes.................

Now, there's only the two track sets & turret to print!
Dave

 

[Dave Ward]

A total of 15 hours printer time the AMC 35.............

The backs of the tracks need a lot of clean up to get a good fit on the hull, but otherwise not at all bad - scaled up to 1/35 from 1/56. Meanwhile the Monoprint is muttering in the background, printing a 1/35 Japanese Type 94 Tankette. This printer is slow, but since I restored it to life, it hasn't missed a beat - I haven't even levelled the bed in a month or so. The bed is rather small, so, if I print 1/35, I have to look around!
I look for tank models with separate tracks - i.e. hull, left track, right track, turret. It's easier to print tracks flat on their backs - it minimises overhangs and the need for supports - it often means that the back of the tracks has little detail - but these are against the tank hull, so it's not obvious
Dave

 

[Dave Ward]

The Monoprice has just finished printing one of the tracks of the Type 94 & it doesn't fit the hull! The problem is, I don't know which is wrong. The model is scaled up from 1/100, and I suspect I dyslexed one of the scaling factors. I've resliced the models, but printing will have to wait until tomorrow. I'm surprised I haven't done this before very easy to do!:confounded:
Dave

 

[Dave Ward]

Lazy day, looking on the 'net for models. I have found a Ferret ( I know Airfix are putting out a model in the summer ), and two models that have been produced in plastic, Tetrarch & M22 Locust - prices for these tiny Bronco models is around the £40 mark, I may print them, although the Locust has nasty tracks & suspension ( print wise )
Dave

 

[Dave Ward]

I've printed out the M22 Locust & the Ferret in 1/35. I think the Locust running gear is about on the limit for my FDM printer - I'll put some pictures up tomorrow - I've tried various settings, but I think I've reached the optimum - if I want any finer, I'll have to drop the nozzle size & that opens a new can of worms.............
I've been fiddling with the Monoprice printer - I sat down & levelled the bed using feeler gauges, so now it is at it's best state. I'm determined not to waste the filament I had trouble with in the Anet & Sunlu. I'm using slow printing speeds & conservative temperatures, - it does mean extended printer times, but it is what it is.
I've found a suitably obscure model for this.................


I'm still not in the best of health, it's like a continuing dose of the 'flu - I find myself nodding off, whilst reading, or watching television. about the only good thing I can say is that my BP is pretty normal & my Diabetic blood sugar level is within it's normal range.
Dave

 

[stillp]

I'm still not in the best of health, it's like a continuing dose of the 'flu

Have you done a Covid test Dave?
Pete

 

[Dave Ward]

Pictures of the output from two printers - all in 1/35...............


Ferret - with supports still attached - the tyres look OK, but I would have expected a more off-the-road profile


Type 94 Tankette - a bit of clean up to remove those whiskers. Not a machine for the claustrophobic!


M22 Locust, with supports still on - the 30 calibre mg will need replacing - overscale and a drum magazine (?)

The Locust tracks printed on the Monoprice. Really more suited to resin printing! I slowed the print right down & each track took over four hours to print each. They are fragile & need a lot of clean up - I managed to break off part of the drive sprocket ( bottom right )

The track links are pretty well defined - even though they may look rough at this magnification!


Citroen-Kegresse P28 Armoured Car. I printed the hull with my troublesome white satn PLA - the Monoprice seems to be forgiving with it's feed - so that spool isn't wasted!
It's easy to find models on the internet, but to find models of lesser known vehicles is a bit more difficult, and of those that are suitable for FDM, even trickier. Sometimes what looks good, when printed looks horrible! I printed out a 250 mm liner & the result was really hideous! Trouble was the supports hid all the flaws, so not seen until the print had finished. You have to accept that certain things won't print - unsupported gun barrels for one!
As can be seen - all these prints need clean up, some more than others - it's very much like dealing with a limited run kit from a decade ago!
The output from Copper State Models is proving that resin printing can be extended to more than accessories. To produce an injection moulded model, you have to produce the CAD model & then have expensive injection moulds made, before producing anything. The resin printing process cuts out the mould making. At the moment resin isn't really feasible for large parts - like 1/32 aircraft wings & fuselages, but I can see that being overcome.
Dave

 

[Dave Ward]

Have you done a Covid test Dave?
Pete

Yep,Negative
Dave

 

[Richard48]

Ferret looks top notch Dave.You certainly are banging this stuff out.Hope the flu bug off soon.
Take it easy.
Richard